Self-Assembling Assemblers

ABSTRACT

A machine that is capable of assembling a copy of itself from a feedstock of parts is described. The machine operates on a lattice or grid on which it is able to move and from which it receives power and control signals. The machine (assembler) is composed of modules that each perform some functionality. In the simplest case, only three module types are needed: a linear step module, a gripper, and an anchor. The linear step module is capable of moving from one lattice location to the next, the gripper module is capable of gripping other modules, and the anchor module is capable of attaching the machine to the grid. With these three primitives it is possible for this simple machine to move on the grid using inchworm-like motions, pick up other modules, and assemble a copy of itself.

This application claims the benefit of U.S. Provisional Application No. 62/158,343, filed May 7, 2015, the entire disclosure of which is herein incorporated by reference.

This invention was made with government support under Grant/Contract No. NSF CMMI-1344222 awarded by NSF. The government has certain rights in the invention.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to robotic assembly, and more specifically to self-assembling assemblers.

BACKGROUND OF THE INVENTION

Skidmore et al. have proposed a concept for an array of self-assembling micro-manipulators. They show exponential assembly through the sequential fan-out of manipulators assembling other manipulators and show that in N steps the system can assemble 2^(N) manipulators. [G. D. Skidmore, E. Parker, M. Ellis, N. Sarkar, and R. Merkle, “Exponential assembly,” Nanotechnology, vol. 12, no. 3, pp. 316-321, September 2001.] This concept, however, requires pre-fabricated sheets of component parts and is not capable of making arbitrary structures. Pelrine et al. have demonstrated a system in which many robots controlled in parallel can work together to build structures. The system is comprised of a substrate with carefully routed electrical traces and permanent magnet “robots” which levitate above the substrate and are controlled by a central processor. [R. Pelrine, A. Wong-foy, B. Mccoy, D. Holeman, R. Mahoney, G. Myers, J. Herson, and T. Low, “SRI Robot Swarm,” 2012.] A NASA Institute for Advanced Concepts report details some concepts and guidelines for the design and development of self-replicating systems. [T. Toth-Fejel, “Modeling Kinematic Cellular Automata Final Report,” pp. 1-74, 2004.]. Of these, the Moses Universal Constructor [M. Moses, “A Physical Prototype of a Self-replicating Universal Constructor, University of New Mexico, 2001] has come closest to physically realizing a self-assembling system but was limited because the feedstock was overly complex and did not allow for the construction of strong, scalable systems.

This invention describes a robotic assembler, a “robosome,” that can assemble almost anything, including itself.

The complexity and diversity of life is based on an inventory of just twenty parts, the common amino acids, which are combined by the ribosome to create the range of molecular machinery. Their discrete construction allows errors to be detected and corrected, global geometry to be determined by local constraints, and the scalability of ribosomes making ribosomes. This invention brings these attributes into regimes of engineered materials that are not available in molecular biology.

This invention is accomplished by developing a basis set of building blocks that are inorganic analogs to amino acids. Instead of basic vs. acidic, hydrophobic vs. hydrophilic, . . . , these are conducting vs. insulating, ferromagnetic vs. ferroelectric, . . . . They are linked by mechanically reversible joints analogous to bonds, with a workflow to design with them and plan their placement. The assembler is initially conventionally constructed, and then in stages its components will be replaced with the parts that it's assembling. The assembler is essential to this roadmap, and is itself a paradigmatic test case for the integration of a functional system.

The outcome of the invention is digitized fabrication, analogous to the earlier digitization of communication and computation, by embodying codes in the construction of materials. Beyond the current focus in advanced manufacturing on additive versus subtractive processes, this invention introduces a much more fundamental transition to assembly and disassembly. Potential disruptive benefits include a radical simplification of material supply chains down to a small number of feedstocks, and the ability to exponentially ring up manufacturing capacity on demand.

Benefits of building functional systems with assemblers that assemble assemblers include:

-   -   Saving time: the time for a product to go from component         vendors, to OEMs, to inventory, to delivery can be replaced by         production in the field.     -   Simplifying supply: large inventories and long supply chains to         remote locations can be replaced by assemblers fed by a standard         set of parts.     -   Rapid customization: because assembly is done on demand, what is         produced can be dynamically modified to match a mission.     -   Increasing integration: technology today is poorly integrated         across length scales; by spanning them with a common process,         size and weight can be reduced, and related capabilities         combined.     -   Eliminating waste: unneeded products can be disassembled to         their constituent components and reused, rather than disposed.     -   Adding capacity: because assemblers can be tasked to build other         assemblers, manufacturing capacity can be increased         exponentially rather than linearly to meet demand.     -   Adapting designs: by retaining assemblers as part of the systems         that they assemble, they can become reconfigurable to adapt to         dynamically changing requirements. Alternative approaches         include:     -   3D printing: This is currently receiving a great deal of         attention, but is limited in the range of properties compatible         with a multimaterial printing process. Expensive inks are needed         for good conductors, and semiconductors show poor carrier         mobility. The approach taken here can instead assemble elements         made from bulk electronic materials.     -   IC fabrication: Chip fabrication requires millions of dollars         for mask sets, billions of dollars for fabs, and turn times of         many months. The approach taken here does not aim to compete         with the incremental cost per chip following that investment of         time and money; it targets significantly reducing both the time         and cost for quickturn, lowrate production. Existing chip fab is         also limited to on the order of ten metal layers; the assembly         approach aims to significantly increase complexity with a         fundamentally three-dimensional process.     -   Electronics manufacturing: The pick-and-place machines used to         assemble circuit boards are two-dimensional and analog parts can         be placed in arbitrary locations on boards. The task of the         three-dimensional assembler to be developed is simplified by the         discretization of the material, quantizing the motion system to         relative displacements on a lattice. Also, part feeding is         simplified from large numbers of varying reels to small numbers         of standard shapes.     -   Reconfigurable robotics: This promises universal rather than         special purpose robots, but the smallest pitches have been on         the order of a centimeter, and the number of modules in the         range of tens to hundreds, limited by the demanding system         integration required. The assembler to be developed is a new         kind of reconfigurable robot, building modules out of, rather         than into, the primitive elements.     -   Materials genome: These initiatives have been something of a         misnomer, because they are more like recipes, cataloging how a         wide range of materials can be continuously combined to vary         their properties. The approach to be taken here is much more         like a genome, with a small set of basis components.     -   Self-assembly: the complexity that can be attained with         self-assembly is limited by diffusional time scales, error         accumulation, and an exponential difficulty in coordination.         Biological assembly, like this invention, is better understood         as coded rather than self-assembly, with messenger RNAs bringing         instructions, transfer RNAs bringing parts, joints being made in         the ribosome, and chaperones guiding folding.

This invention mandates revisiting decades of assumptions and historical practices about the nature of design representations, material specifications, manufacturing process planning, and machine and motion control. The “robosome” assemblers are a new kind of relative robot, that functions as a part of the structure that it's assembling. This process will be reversible, replacing disposal with disassembly and reuse.

The most profound question posed by this invention is what the minimum requirements are to bootstrap a technological civilization. Models for in-situ resource utilization typically recapitulate the stages of the industrial revolution; this invention can instead be thought of as the technological equivalent of the evolution of the building blocks for life. The results will be particularly relevant for operations in remote, resource constrained, and rapidly changing environments that cannot assume existing support infrastructure.

SUMMARY OF THE INVENTION

The primary goal of this invention is to develop an assembler that can assemble itself out of the parts that it is assembling. This will be realized by developing engineering analogs to amino acids. The twenty standard amino acids are discretely combined to create the molecular machinery in living systems, ranging from the motors in muscles, to the photoreceptors in eyes, to the synapses in brains. Likewise, a set of universal building blocks for engineered systems has been developed through this invention.

Just two part types, conducting and insulating, will replace the layers, traces, and vias in printed circuit boards, along with the connectors on them and wiring between them. At a finer pitch, those same two parts are assembled into inductors and capacitors, which are then combined into RF matching networks and antennas. A third resistive part type will be added to assemble resistors with variable values, form factors, and current capacities, replacing the roughly 500,000 resistor types in the electronic inventory today. Semiconducting part types are added to assemble discrete and then integrated logic, flexural part types to assemble mechanisms, and magnetic and piezoelectric part types for actuation.

This discrete set of parts are linked by reversible joints. These are spatial analogs to digital codes, allowing global geometries to be determined by local constraints, placement errors to be detected and corrected, and disassembly and reuse of the parts.

Three-dimensional interconnect and integrated circuits, and optical metamaterials are example uses of the invention. The invention can be used for manufacturing at the end of long supply chains, such as for reconfiguring spacecraft hardware.

The automated assemblers described herein are essential for realizing this roadmap. They are constructed from conventional machine components, and then in stages are replaced by the parts being assembled. There is utility in shrinking feature sizes, with a larger assembler producing a smaller one. But the primary focus on assembling the assembler is for the essential role that that plays in scaling. Rather than seeking linear increases in assembly speed or parallel part placement, the ultimate result will be an exponential increase in the number of assemblers, like the exponential increase in the number of cells in a bioreactor.

This invention encompasses an assembler that assembles assemblers. The invention can be understood as a “robosome,” a robotic ribosome. Like the essential role of the ribosome in making all other proteins, the invention is a universal machine to make machines, including itself.

The invention is based on “digital” materials which are reversibly assembled from a discrete set of parts, with a discrete set of relative positions and orientations [Digital Materials for Digital Printing, G. A. Popescu, N. Gershenfeld, and T. Mahale, D F 2006 International Conference on Digital Fabrication Technologies, Denver, Colo. (2006)] These attributes allow metrology to be local, so that an assembler can make something larger than itself; errors to be detected and corrected, so that an assembler can make something more accurately than its own positioning; heterogeneous materials to be joined in a common process, and objects to be disassembled and reused rather than disposed. The assembled structures can behave as bulk materials with effective properties beyond those of existing materials [Reversibly Assembled Cellular Composite Materials, Kenneth C. Cheung and Neil Gershenfeld, Science (341), pp. 12191221 (2013)].

Assembler primitives can be assembled from just four part types. Piezoelectric blocks are used in pairs to create a walking motion in the linear motion axis. A microgripper, which can manipulate the blocks it is made of, is formed as a flexural linkage which amplifies the expansion of the piezo actuators. A clamping device can be made which can secure the assembler to the lattice. With these three primitive functions, an assembler can be made that can move on a lattice, pick up, and place its own parts.

The heart of this invention is the development of engineering analogs to amino acids. A wide range of molecular machines, such as the motor proteins in muscles and the light-sensing molecules in the eye, are made from twenty common amino acids. Each contributes a fundamental property, like hydrophobicity versus hydrophilicity, that can be combined to create complex functions. They are built by the ribosome according to assembly sequences carried by messenger RNAs. Rather than being based on biochemistry, the building blocks in this invention span the attributes of engineered materials, with again on the order of twenty parts types, including rigid and flexible, conducting and insulating, majority and minority carriers, and saturated and permeable magnetization. These are mechanically linked by reversible joints that serve as bonds.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an assembler composed of modular parts.

FIG. 2 shows a self-assembling assembler simulation.

FIG. 3 shows the assembler crawling on the grid above and placing parts below layer by layer.

FIG. 4A is a microgripper assembled from simple part-types.

FIG. 4B is a cross-sectional view of the microgripper of FIG. 4A.

FIG. 5 is an anchor module gripping attachment points on the grid.

FIG. 6A is detail of a linear translator actuator block (piezo bimorph driven linear inchworm motor.

FIG. 6B is a cross-sectional view of the linear translator actuator block shown in FIG. 6A.

FIG. 7 shows the details of some of the block types.

FIG. 8A is a block diagram for a distributed architecture of parallel assembly.

FIG. 8B is a distributed architecture for parallel assembly.

FIG. 8C is a top view of the lattice of the distributed architecture of parallel assembly.

FIG. 9 is the hierarchical decomposition of the assembled systems.

FIG. 10A depicts an assembler before placing a part.

FIG. 10B depicts the assembler of FIG. 10A with its gripper module lowered to place a part.

FIG. 11 is a taxonomy of brick-types at each level of hierarchy.

FIG. 12 shows the hierarchy from parts to functions to modules to systems.

FIG. 13 illustrates functional bricks from which mechanisms and robotic modules can be assembled.

FIG. 14 illustrates a natural hierarchy enforced as blocks are assembled into higher-level parts via a piezoelectric block example.

FIG. 15A shows a cutaway of two leg-modules situated below a build-stage.

FIG. 15B depicts a leg module in a retracted configuration.

FIG. 15C depicts a leg module engaged with a build-stage.

FIG. 16 shows robot composition.

FIG. 17A shows an assembled piezo linear actuator.

FIG. 17B shows how functions can be decomposed into constituent parts.

FIG. 17C shows the piezo linear actuator made up of its constituent parts.

FIG. 18 shows an alternate geometry for functional parts.

FIG. 19 shows a system assembled from hexagonal functional tiles.

FIG. 20 shows an envisioned system capable of assembling another assembler like itself.

FIG. 21 depicts parts feeders at the edge of the grid and a build-stage with an additional degree-of-freedom to enable the assembly of arbitrary 3D structures.

FIG. 22 shows an alternate arrangement allowing for the assembly of more assemblers where another external z-axis is used.

FIG. 23A is a prototype of a larger scale version of the piezo linear actuators described in FIG. 17A.

FIG. 23B shows an enlarged section of a prototype of a larger scale version of a piezo linear actuator.

FIG. 23C depicts a microgripper prototype at a larger scale.

FIG. 24A shows a microgripper pickup test, as the microgripper is about to pickup an object.

FIG. 24B shows a microgripper pickup test, after the microgripper has picked up an object.

FIG. 25 shows a transistor mounted onto a building block.

FIG. 26A illustrates a microstepper motor.

FIG. 26B shows the lattice on which the assemblers locomote.

FIG. 26C is a blown up diagram of a mobile assembler.

DETAILED DESCRIPTION OF INVENTION

The invention describes a machine that is capable of assembling a copy of itself from a feedstock of parts. The machine operates on a lattice or grid on which it is able to move and from which it receives power and control signals. FIG. 1 shows the assembler 102 composed of modular parts. The machine (assembler) 102 is composed of modules that each perform some functionality. In the simplest case, only three module types are needed: a linear step module 104, a gripper 108, and an anchor 106 (FIG. 1). The linear step module 104, or linear actuator block 104, expands by one unit cell along its length and is capable of moving from one lattice location to the next. The gripper module 108, or gripper block 108 reversibly attaches to other blocks so they may be “picked” and “placed” and is capable of gripping other modules. The anchor module 106, or anchor block 106, attaches to the grid on which the assembler crawls, and is capable of attaching the machine to the grid. With these three primitives it is possible for this simple machine 102 to move on the grid using inchworm-like motions, pick up other modules, and assemble a copy of itself (FIG. 2). FIG. 2 depicts a self-assembling assembler simulation, and shows a feedstock of modules 202, an assembler going to pick up a block 204, an assembler placing a block 206, and an assembler being built 208.

These primitives enable locomotion and assembly on a two-dimensional grid. To enable three-dimensional assembly an alternative configuration may be used in which the assemblers still locomote on a two dimensional grid but place parts layer by layer to build three-dimensional structures. In this embodiment, the assembler crawls on the underside of the grid and place parts below it (FIG. 3). In FIG. 3, the assembler 302 crawls on the grid above and places parts 304 below layer by layer.

Initially the modules are built using conventional fabrication means (either subtractively or additively). Actuation may be accomplished, for example, using electromagnetics, electrostatics, piezoelectrics, or thermally.

To scale the system both up in complexity and down in length-scale, the modules themselves are made from a feedstock of smaller, simpler parts (referred to as blocks). The feedstock of parts, for example, may consist of a structural block, a conductive block, a piezoelectric block, and a flexural block. FIG. 4A illustrates how a micro-gripper 400 module may be assembled from a feedstock of simple block-types. The microgripper 400 is made of conductive 402, piezoelectric 404, flexural 406, and structural 408 parts. In this example, a compliant mechanism is made through the strategic placement of flexural and rigid elements such that the expansion of the piezoelectric blocks at the base of the mechanism are converted into a gripping motion at the tips. FIG. 4B is a cross-sectional view of the microgripper of FIG. 4A. An anchor module 500 and a linear step module 600 are depicted in FIG. 5 and FIG. 6A, respectively. The anchor module 500 is gripping attachment points 504 on the grid, and grips the lattice using a compressive force at multiple points 504 generated from the expansion of the piezoelectric blocks 502. FIG. 6A shows the detail of a linear actuator block 600 (piezo bimorph driven linear inchworm motor). The linear step module 600 is a compliant linear mechanism which moves relative to its base via the periodic expansion and contraction of alternating sides of piezo bimorph actuators. FIG. 6B is a cross-sectional view of the linear translator actuator block shown in FIG. 6A.

The blocks themselves may be either a single material or a composite of multiple materials. FIG. 7 illustrates some of the block-types in further detail. Block types can be conductive 702, structural 712, piezoelectric 722, or flexural 732. Joints between the blocks are made with interlocking geometric features. The conductive 702 and structural 712 blocks provide four in-plane connections and are composed of a single bulk material (e.g., fiberglass for structure and copper for conductivity). The piezoelectric 722 and flexural 732 block provide only two in-plane connections and are composed of multiple materials in order to achieve the desired functionality. In this embodiment, the piezoelectric block 722 is made up of copper 724 and PZT 726, and the flexural block 732 is made up of fiberglass 734 and nitinol 736.

FIG. 8A shows a block diagram for an embodiment of a distributed architecture of parallel assembly 800. In implementing the control of the system, it's desirable to have a central processor 802 containing logic 803 and power 804 responsible for coordinating the many assemblers 810 to enable the parallel assembly of a single structure. In a specific implementation, a centralized “build queue” may represent all of the parts that need to be placed. When an assembler 810 is done with its previous task, it pulls a new job from this centralized build queue and executes the specific task (e.g., place a gripper module 808 at x=40, y=50). This central processor 802 may also be responsible for the control of the individual actuators 806 or anchors 809 within an assembler 810 or it may hand-off that control to a sub-processor 807 onboard each assembler (FIG. 8A). Because the system is based on centralized control through the grid 805 and assemblers take discrete steps on a known lattice 805, it can be run without any closed-loop feedback. The position of the assemblers 810 on the grid 805 is known deterministically from the history of movement/control commands sent to them.

FIG. 8B shows a distributed architecture for another embodiment of parallel assembly 850. Each assembler 852 is a simple machine with only a few degrees of freedom and is capable of carrying a single part and moving from one lattice location 856 to the next. The assemblers 852 receive power and control instructions from the substrate that they locomote on. At the edge of the substrate, magazines store a feedstock 854 of different part-types. A global z-axis raises the build-platform as each layer is populated by the mobile assemblers 852. FIG. 8C is a top view of the lattice of the distributed architecture of parallel assembly 850.

FIG. 9 shows the hierarchical decomposition of the assembled system. The hierarchical decomposition of the assembled systems is analogous of the primary, secondary, tertiary, and quaternary structure of proteins. At the top level of the hierarchy is the system 902, composed of several microgrippers 904. The global z-axis 906 raises the build-platform as each layer is populated by the mobile assemblers. At the second level of the hierarchy are the modules 912, including a walking leg module 914. Depicted at this level is a leg motion sequence 916. At the third level of the hierarchy is the function 922 of the module, which can include a piezo shear actuator 924. At the bottom of the hierarchy is a part 932, which is a piezoelectric element 934.

FIG. 10A depicts the assembler before placing a part, while 10B depicts the assembler with its gripper module lowered to place a part.

FIG. 11 is a taxonomy of brick-types at each level of hierarchy. Parts 1102 can be mechanical (including structural, flexible, and/or expanding—e.g., thermal, piezoelectric), electrical (including conductive, insulating, and/or resistive), semiconducting (including N−type, P−type, N+type, and/or P+type), or magnetic (including soft, hard, and/or ferromagnetic). Functions 1104 can be mechanical-passive (including revolute, prismatic, and/or spring), mechanical-active (including bending, shearing, longitudinal, and/or transverse), electrical-passive (including conducting, insulating, resistive, capacitive, and/or inductive), or electrical-active (including transistor and/or diode). Modules 1106 can be motion constraint (including large disp. linear and/or large disp. revolute), motion generation (including walking, inching, and/or gripping), electronic (including digital—logic, flip flop, latch, oscillator and/or analog—boost, op-amp). Systems 1108 can be mechatronic (including linear axis, rotary axis, micro-gripper, and/or assembler) or computing (including sequencing, sampling, processing, and/or memory).

FIG. 12 depicts the hierarchy from parts (1202) to functions (1212) to modules (1222) to systems (1232). In this case, item 1202 shows how a linear piezo actuator function is assembled from conductive and flexural parts. Item 1212 is the linear piezo actuator which deforms longitudinally when voltage is applied to it. Item 1222 shows a walking leg module (similar in function to the item labeled “walking leg module” in FIG. 9) which is constructed from many piezo actuators (as well as other functional parts). Finally, item 1232 is showing a section/cutaway of an alternate assembler configuration wherein the leg modules (item 1222) are used to move a linear degree-of-freedom. The assembly of parts in the upper section of item 1232 is a new module being assembled and the assembly of parts below that is the walking leg module (item 1222). Importantly, the arrow between item 1222 and item 1232 is pointing point to the leg module rather than the part being assembled.

FIG. 13 shows functional bricks. The invention focuses on the development of functional bricks from which mechanisms and robotic modules can be assembled. These bricks include functions such as hinge joints, actuation, conductivity, and structure. Item 1302 is a piezo linear actuator. Item 1304 is a double-hinge joint or “shear joint” which allows a shear and rotational degree-of-freedom. Item 1306 is a displaced/deformed version of item 1304. Item 1308 is a rotary hinge joint. Item 1310 is a displaced/deformed version of item 1308. Item 1312 shows how the functional bricks interlock.

There is a natural hierarchy enforced as blocks are assembled into higher-level parts, which then become blocks to assembler even higher-level functionality. In FIG. 14, a piezoelectric block 1402 is a part of a large-displacement linear actuator mechanism 1404, which is, in turn, part of a walking leg mechanism 1406, which, in turn, is part of an assembler stage 1408.

It's possible to use multi-scale parts with features that connect parts of different sizes. This enables sparsity in the lattice where density is not needed and increases potential build speed. To estimate assembly speed, assume 1 k×1 k×1 k addressable volume elements, comparable to the dynamic range of a typical 3D printer. With a part placement rate of 1 kHz, comparable to the drop frequency in ink-jet printing, it would require 11 days to full this volume. Two approaches will be used to accelerate this. The first recognizes that, like video coding, what's being transmitted to the assembler is not a random pattern. There's a natural hierarchical decomposition of a design into larger blocks with repeated properties. The analog of a pyramidal coder is multi-scale parts, with mating features across length scales. A 100:1 compression ratio reduces the build time to a few hours, comparable to typical 3D printing.

Through the arrangement of the functional bricks, more complex mechanisms can be assembled. For example, FIG. 15A-C illustrates a walking motor which moves the stage above it through the sequential firing a series of piezo actuator bricks. FIGS. 15A-C show the same walking leg module 1222 depicted in FIG. 12. FIG. 15A shows a cutaway of two leg-modules 1222 situated below a build-stage (on which new modules/systems are built). FIG. 15B depicts the leg module in its retracted configuration. FIG. 15C depicts the leg module 1222 engaged with the build-stage 1502. The leg modules 1222 work by synchronously walking the build-stage 1502 to the left or right (looking at FIGS. 15B/C) such that one leg is always engaged (FIG. 15C).

FIG. 16 shows that these mechanisms can then be composed to form robots which are themselves capable of assembling the parts they are made out of.

FIGS. 17A-C shows the assembly of functional bricks. Through the development of robots with fine placement capabilities, the functional bricks themselves may be assembled from even more primitive single material building blocks. FIG. 17A-C show the same piezo linear actuator described by items 1202 and 1212 of FIG. 12. Expansion of the piezo bricks vertically creates an amplified deformation of the part, horizontally. This is showing how functions can be decomposed into constituent parts (in this case conductive, flexural, piezo, and insulating). FIG. 17A shows an assembled piezo linear actuator. FIG. 17B shows how functions can be decomposed into constituent parts. FIG. 17C shows the piezo linear actuator made up of its constituent parts.

FIG. 18 shows an alternate geometry for functional parts. Item 1802 is a basic insulating/structural part. Item 1804 is a revolute joint. Item 1806 is a piezo linear actuator (which functions the same as FIG. 17A-C). Item 1808 is an isometric view of the same part showing that the connections between parts are made with conductive press-fit sockets with both a male and a female end (item 1810).

FIG. 19 shows a system assembled from the hexagonal functional tiles. With these primitives, a large stroke linear actuator with motion constrained by a linear flexure stage can be assembled (item 1906). Item 1902 depicts the large stroke linear actuator with motion unconstrained by a linear flexure stage. In this case, piezo actuator blocks (which are centrally located in the system) cause the linear motion degree-of-freedom to deform and engage with a toothed profile (item 1904). This could be used as the clutch in an inchworm drive mechanism, for example. Item 1908 is a blown up pivot section of the large stroke linear actuator with motion constrained by a linear flexure stage shown by item 1906.

FIG. 20 shows an envisioned system capable of assembling another assembler like itself. It is composed of four identical linear actuator blocks 2002, enabling it to move on a grid 2004 in X and Y and also pick and place blocks with its Z axis. Each block 2002 has a microcontroller coordinating the motions. Power and control is sent through the grid 2004 that the assemblers latch into and operate on. FIG. 21 depicts this environment including parts feeders 2006 at the edge of the grid 2004 and a build-stage 2008 with an additional degree-of-freedom to enable the assembly of arbitrary 3D structures. FIG. 22 shows an alternate arrangement (blocks 2002, grid 2004, parts feeders 2006, build stage 2008) allowing for the assembly of more assemblers where another external z-axis 2010 is used.

FIGS. 23A-C show module prototyping. FIG. 23A is a larger scale version of the piezo linear actuators described in FIG. 17A, for example. It uses a conventional piezo stack actuator and houses it in a stainless steel flexure mechanism made using wire-edm. The flexure mechanism amplifies the stroke of the piezo stack by 20×. FIG. 23B shows an enlarged section of a prototype of a larger scale version of a piezo linear actuator. FIG. 23C depicts a microgripper prototype, again at a larger scale. The same amplifying mechanism is used to increase the stroke of the piezo actuator but in this case produce a displacement of gripper tips. FIG. 24A shows the microgripper pickup test, as the microgripper 2402 is about to pickup an object 2404. FIG. 24B shows the microgripper pickup test, after the microgripper 2402 has picked up an object 2404. FIG. 25 shows a transistor 2502 mounted onto a building block 2504 reflecting another geometry.

FIG. 26A-C shows a mobile assembler model. FIG. 26A illustrates a microstepper motor. FIG. 26B shows the lattice on which the assemblers locomote. FIG. 26C is a blown up diagram of a mobile assembler, showing the bearing surface 2602, solenoid 2604, gear/foot 2606 and microstepper motor 2608. The rotary crawler has two controlled degrees of freedom and two one-bit actuators 2604. The assembler locomotes by clamping one foot 2606 to the substrate, releasing the other, and swinging about the clamped foot 2606. The one-bit actuators are solenoids 2604 that allow each foot 2606 to clamp or release from the substrate. Microstepper motors 2608 are used to provide controlled rotation of the body.

While the above specification and examples provide a description of the invention, many embodiments of the invention can be made without departing from the spirit and scope of the invention. It is to be understood that the foregoing embodiments are provided as illustrative only, and does not limit or define the scope of the invention. Various other embodiments are also within the scope of the claims. 

What is claimed is:
 1. An apparatus capable of assembling a copy of itself from a feedstock of parts as building blocks, the apparatus operating on a lattice or grid on which it is able to move and from which it receives power and control signals, comprising: a linear step actuation module capable of moving from one lattice location to the next; a gripper module capable of gripping other modules and parts; an anchor module capable of attaching the apparatus to the grid; wherein the feedstock of parts consists of a structural block, a conductive block, a piezoelectric block, and a flexural block.
 2. The apparatus of claim 1, wherein the gripper module comprises tips, and is composed of flexural and rigid elements coupled to a piezoelectric block such that a gripping motion at the tips is formed when the piezoelectric block receives electrical potential, and whereby the gripper module reversibly attaches to other blocks so they may be picked and placed.
 3. The apparatus of claim 1, wherein the anchor module grips the lattice using a compressive force at multiple points generated from the expansion of piezoelectric blocks which comprise the anchor module.
 4. The apparatus of claim 1, wherein the linear step actuation module moves relative to its base via the periodic expansion and contraction of alternating sides of piezo bimorph actuators, and expands by one unit cell along its length.
 5. The apparatus of claim 1, wherein the modules enable locomotion and assembly on a two-dimensional grid.
 6. The apparatus of claim 1, wherein the apparatus enables three-dimensional assembly through a plurality of assemblers locomoting on a two dimensional grid that place parts layer by layer.
 7. The apparatus of claim 6, wherein the apparatus crawls on the underside of the grid and places parts below it.
 8. The apparatus of claim 1, wherein each of the modules is built using conventional fabrication means, either subtractively or additively.
 9. The apparatus of claim 1, wherein actuation of each module occurs using electromagnetics, electrostatics, piezoelectrics, or thermally.
 10. The apparatus of claim 1, wherein the blocks consist of a composite of multiple materials.
 11. (canceled)
 12. The apparatus of claim 1, wherein the conductive and structural blocks provide four-in-plane connections and are composed of a single bulk material.
 13. The apparatus of claim 12, wherein the single bulk material is fiberglass for structure, and copper for conductivity.
 14. The apparatus of claim 1, wherein the piezoelectric and flexural blocks provide two in-plane connections and are composed of multiple materials.
 15. The apparatus of claim 1, wherein the piezoelectric block is made of copper and PZT.
 16. The apparatus of claim 1, wherein the flexural block is made of fiberglass and nitinol.
 17. The apparatus of claim 1, wherein the parts respectively provide the functions of hinge joints, actuation, conductivity, and structure.
 18. The apparatus of claim 1, wherein the parts comprise joints, said joints are made with interlocking geometric features.
 19. The apparatus of claim 1, wherein parts are reusable after disassembly.
 20. A system of distributed parallel assembly, comprising: a lattice or grid; a plurality of assemblers, each containing a sub-processor, operating on the lattice or grid on which they able to move and from which they receive power and control signals, wherein each of the plurality of assemblers is capable of assembling a copy of itself from a feedstock of parts as building blocks under control of the control signals; and a central processor containing logic and power, responsible for coordinating the plurality of assemblers through the production of control signals to enable the parallel assembly of a single structure; wherein the system communicates centralized control through the lattice or grid to the plurality of assemblers whereby they may take discrete steps on the lattice or grid.
 21. The system of claim 20, wherein the system operates without any closed-loop feedback.
 22. The system of claim 20, wherein the position of the plurality of assemblers on the grid is known deterministically from the history of movement/control commands sent to them.
 23. The system of claim 20, having a centralized build queue that represents all of the parts that need to be placed, such that when an assembler finishes a previous task, it pulls a new job from the centralized build queue and executes another task.
 24. The system of claim 20, wherein the central processor hands-off control to the sub-processor onboard each of the plurality of assemblers.
 25. The system of claim 20, wherein each of the plurality of assemblers comprises: at least one actuation module capable of moving from one lattice location to the next; a gripper module capable of gripping other modules; and at least one anchor module capable of attaching the apparatus to the grid.
 26. The system of claim 20, wherein each of the plurality of assemblers functions by carrying a single part and moving from one lattice location to the next.
 27. The system of claim 20, wherein at the edge of the grid, a plurality of magazines stores a feedstock of different part-types.
 28. The system of claim 20 further comprising a build platform that has a z-axis, and control signals include a signal to move the platform along such axis so as to permit a layer-by-layer build by the plurality of assemblers.
 29. An apparatus comprising: a linear step actuator module; a gripper module; an actuator module; wherein the apparatus is capable of constructing a variety of systems, each system comprising a plurality of modules, each module implementing a particular functional brick, each functional brick implemented through the assembly of building blocks as parts.
 30. The apparatus of claim 29, wherein the modules are motion constraint, motion generation, or electronic, and wherein the motion constraint modules are large disp. linear or large disp. revolute, the motion generation modules are walking, inching, or gripping, and the electronic modules are digital or analog, and wherein the digital modules are logic, flip flop, latch, or oscillator, and the analog modules are boost or op-amp.
 31. The apparatus of claim 29, wherein the functions are mechanical-passive, mechanical-active, electrical-passive, or electrical-active, and wherein the mechanical-passive functions are revolute, prismatic, or spring, the mechanical-active functions are bending, shearing, longitudinal, or transverse, the electrical-passive functions are conducting, insulating, resistive, capacitive or inductive, and the electrical-active functions are transistor or diode.
 32. The apparatus of claim 29, wherein the parts are mechanical, electrical, semiconducting, or magnetic, and wherein the mechanical parts are structural, flexible, or expanding, wherein the expanding parts are thermal or piezoelectric, the electrical parts are conductive, insulating, or resistive, the semiconducting parts are N−type, P−type, N+type, or P+type, and the magnetic parts are soft, hard, or ferromagnetic.
 33. The apparatus of claim 29, comprising an assembler stage, said stage comprising a walking leg mechanism, said mechanism comprising a large-displacement linear actuator mechanism, and said actuator mechanism comprising a piezoelectric block.
 34. The apparatus of claim 29, wherein a walking motor module moves a stage above it through the sequential firing of a series of piezo actuator bricks.
 35. The apparatus of claim 29, where assembled mechanism are composed to form robots which are themselves capable of assembling the parts they are made out of.
 36. The apparatus of claim 29, wherein the parts comprise hexagonal tiles embedded with functions including rotary flexure, and linear actuation.
 37. The apparatus of claim 29, wherein a functional brick is a large stroke linear actuator with motion constrained by a linear flexure stage.
 38. The apparatus of claim 29, wherein each of said plurality of modules, functional bricks and building blocks comprises a first size scale and a second size scale, wherein the first size scale is larger than the second size scale. 